Raising mechanism



30, 1930. H. F. FLOWERS 1,737,342

RAISING mzcrumxsm il N 25. 1926 5 Sheets-Sheet. 1

Dec. 30, 1930. H. F. FLOWERS 1,787,342

RAISING MECHANISM Filed Nov. 23. 1.926 5 Sheets-Sheet. 2

Dec. 30, 1930. H. F. FLOWERS 1,787,342

RAISING MECHANISM Filed Nov. 23, 1926 3 Sheets-Sheet 5 ew v a .9

PATENT OFFICE HENRY FORT FLOWERS, OI FINDLAY, OHIO RAISING MECHANISMApplication filed November 28, 1928. Serial No. 150,329.

This invention concerns improvements in raising mechanism and isparticularly adapted for tilting the dump body of a vehicle.

It has heretofore been proposed to assemble such mechanism in variousconstructions, and screw devices have been employed which are actuatedfrom the prime mover such as the automobile engine when the mechanism isemployed on a dump truck.

I The present invention presents a structure which is compact and iseasily located in the space between the vehicle framing and the bodyfloor, without projecting parts which might interfere with the passageof the vehicleover an uneven route. To this end, a

plurality of screws are threaded one into another for progressiveextension.

Another feature is the provision of an automatic oiling system for themechanism 7 whereby lubrication of all working surfaces is assured.

A further feature is the provision of a structure which may be relievedfrom all transmitted strain of the body load during transport.

Again, all moving parts are enclosed and protected during transport; andextensive bearing surfaces are provided on the screw threads so that apositive support of the body and its load is assured.

A further feature is the permissive slipping of elements when the fullyextended position is reached, so that no breakage of the driving systemoccurs; and this slippage 0ccurs at the point of application of theraising effort to the body, so that the provision and maintenance ofsensitive driving clutches is eliminated.

This structure is well adapted for employment with the tilting and dooroperating structures disclosed in my copending application, Serial No.740,307, filed Sept. 27, 1924.

With these and other objects 1n view, as

will appear in the course of the following specificaton and claims,there is shown on the accompanying drawings:

Fig. 1 is a side elevation with partial sections, showing the raisingmechanism in place on the underframe of a vehicle, with the dump body ina tilted position.

Fig. 1a is a detail view in partial section.

Fig. 2 is a section through the raising mechanism in a collapsedposition, substantially on line 22 of Fig. 4.

Fig. 3 is a detail plan view of the bottom disk of the raisingmechanism.

Fig. 4 is a top view of the raisin mechanism, with the vehicle bodyremoved.

Fig. 5 is a transverse section through the vehicle body and frame,showing the raising'eo mechanism in the lowered position.

The raising mechanism according to the present invention comprises aplurality of screws, threaded one into the other, and with the outerscrew threaded within a rotatable sleeve carried on the frame and withthe inner screw in raising relation to the body. By the actuation of thesleeve, the screws are caused to extend themselves and to tilt thevehicle body, and upon reversal of the direction of such rotation, thevehicle body is permitted to return gradually to its lowered ortransport position.

On the drawings, the underframe of the vehicle is represented by thechannel beams 10 which carry the spacer plates 11 having the pivotbrackets 12 thereon to support the fulcrum 13 about which the sub-framebeams 14 tilt during dumping toward the rear. A vehicle body 15 ismounted on this sub-frame, and may include the side doors 16, and has anend door 17 which may be opened in an appropriate manner for discharglngthe load contained within the body during rearwise dumping. s5

Mounted on the channel irons 10 of the underframe are the wood blocks 18which support the bracket arms 19 of a socket casting 20. This socketcasting 20 has a hemispherical seat opening to its upper surface toreceive the lower ball member 21. An annular retaining collar 22 issecured rigidly to the socket 20 by the bolts 23, and prevents the lowerball 21 being pulled out of its engagement with the socket. At the frontportion of the socket, the latter and its collar 22 are provided with aboss 24 having a stiffened flange 25, with a slot 26 therein; this slotextends substantially in a vertical plane parallel to the length of thevehicle. The ball 21 1 anydirection which is a resultant of suchmovements. The outer surface of the lower ball 21 may be lubricated withrespect to the lower casting 20 through the 'oil cup 7 6a,.

Rotatably mounted in the lower ball 21 is. an outer sleeve 30 which hasthe t otlied ring- .rr n

the same diameter as the lower portion of the recess. in the telescopingsleeve 53 so that it is guided thereby; atthe upward limit of 7 travelof the spindle 56 with-relation to the the rings 36:

31 welded thereto. A racewayili ing the'sleeve30 serves tofsup o 7 Hupon the end-thrust bearing-re le are held in position. by the cag Theserollers 33 rest 'uponl th member 35 which is supported by d I y on theinner surface {0 the lowerball'2l, and permit a freev rotation ofth'ejouter' sleeve 30 even under heavy load. r

The lower M1121 is cut its top portion so that it is not' acomplete'isphere and has thereat an inwardly projecting flange 37 forsupporting a collar 38, which presents the bearing 30a in closeengagement when the sleeve 30, to guide this sleeve for rotation aboutits own axis. This collar 38 is held in place by a series of bolts 40which pass into the flange 37. To assure the sleeve 30 against an upwardmovement in the lower ball, a seating ring 41 is disposed between thelowersurface of the collar 38 and an outwardly pro ecting peripheralflange 42 on the collar 36 itself. A guide bearing 30?) is likewiseprovlded m a recess of the lower ball 21 to guide the extreme lower endof the sleeve 30 and for rotation about its own axis.

A pinion 43, in meshing engagement with the toothed ring 31 is splinedto the Inner end of a stub shaft 44 and is held thereon by a lock nut45. This stub shaft 44 is supported within the guide sleeve 27 by theball bearin s 46. The squared outer end 47 of the stu shaft 46 issecured in one member 48 of a universal joint, whose other member 49 isfastened in a shaft 50 which is in telescoping and splined drivingrelation with an extending hollow shaft 51, which in turn is connectedthrough a suitable gearing with a power plant. This gearing and powerplantare not represented on the drawings, but it will be understood thatwhen the device is employed on an automobile truck, the internalcombustion engine on this truck may serve as the power plant, and anauxiliary gearing be employed to couple this engine to the shaft 51. vThe recess in the outer sleeve 30 at its upper end is reduced in size topresent a shoulder 52, and the wall of the reduced portion of the recessis threaded to receive th corresponding external threads of a tele opingsleeve 53, which at its bottom end has an outwardly projecting flange54; this flange 54 serves to guide the telescoping sleeve 53 during itsmovement with re ation to the outer sleeve .30, and by its engagementwith the shoulder 52 of the sleeve 30, furnishes a osi- 'tive stopagainst the complete upwar removal of the telescoping sleeve 53 from theouter sleeve 30.

This telescoping sleeve 53 is likewise hollow and its recess is reducedin diameter adjacent the upper end to rovide a shoulder 55"; and thereduced P01131011: of the recess is' threaded interiorly to receive athreaded spindle 56.- The spindle 56 carries at its lower end a disk 57which is of substantially prevents'a complete upward withdrawal of thethreaded spindle out of the telescoping sleeve 53.

The upper end of the threaded spindle 56 projects beyond the end of thetelescoping sleeve 53 and has an aperture therein at right angles to itsown axis, through which passes a retaining pin 58. The upper ball 59 isof spherical shape, but is cut away at its bottom so that it is not acomplete sphere. It has a cavity at its top to receive the projectingend 56a of the spindle 56, and a cross aperture to receive the retainingpin 58, so that the u per ball 59 and the spindle 56 are held fixe lytogether under all operative conditions.

The floor 15a of the vehicle has'the stiffening beams 15?), on which iscarried the upper socket casting 60, which has a spherical hollow whichopens to its downward surface to receive the upper ball 59. The upperball is prevented against a complete removal from the upper socketcasting 60 by a collar 61 which is secured to the casting 60 by thebolts 62. It will be noted that the interiorof the collar 61 isspherically formed about a center point removed downwardly from thecenter point of the spherical recess in the upper socket casting 60. Inthis way. when the screw device has been entirely collapsed. the upperball 59 may be withdrawn slightly from contact with the inner walls ofthe upper casting 60, so that no strain is transmitted from the body ofthe vehicle to the lifting mechanism in a transport position.

The lower end of the outer sleeve 30 is preferably closed byia diskmember 65 (Fig. 3), which has an aperture 66 therein to permit thepassage of lubricant for balancing the pressures inside and outside thesleeve 30. This disk 65 likewise has a number of pins 67 with inclinedtops formed therein to receive the corresponding-stop pins 68 on thelower Ind of the doubly threaded sleeve 53 and the pins 68a formed onthe lower end of the spindle 56. The contact of these pins 68 and 68awith the pins 67, after the two threaded members 53 and 56 havesubstantially reached their lowermost position, prevents a furtherdownward movement of the parts and thus avoids the possibility of injuryto mechanism, or a sticking of the several screw threaded members withrespect to each other. The bottom disk 65 has been represented asconnected to the outer sleeve 30 by welding.

At the upper end of the raisin mechanism, a plurality of projecting lugs5 have been formed on the doubly threaded sleeve 53. A-

similar number of pins 76 are embedded in the upper ball casting 59 forengagement with these lugs when the doubly threaded sleeve 53 reachesits predetermined uppermost position, for the similar purpose of formingstops to prevent sticking of the sleeve 53 in its uppermost position.For a similar urpose, the lower end of the spindle 56 has een shown ashaving a flange which serves not only to carry the downwardly projectingteeth 68a. for engagement with the teeth 67, but also to have theupwardly projecting teeth 69 for engagement with the shoulders 55 withinthe threaded sleeve 53, whereby an easy separation of these members isafforded. Similar teeth 69a may be formed on the simi lar flange 57a, ofthe sleeve 53 for engagement with the shoulder 52 of the outer casing"or sleeve 30.

In employment, the chamber within the L hollow lower ball 21 usuallycontains a considerable quantity of lubricant which may be placedtherein through an aperture closable by the plug 70. As the threadedmembers 53 and 56 move up and down, this lubricant may flow from thespace around the sleeve 30 through the aperture 71 into the interior ofthe sleeve 30, and pass downwardly through the apertures 66 to fill thespace between the disk 65 and the inner wall of the lower ball 21, andto rise to a desired level within the outer sleeve 30.. During thesucceeding downward movement of the threaded members 53 and 56, thelubricant is forced upwardly along the walls and threads of the members30, 53 and 56, so that during the next outward and upward movement, allof the threads are thoroughly lubricated, and

maintained with surfaces having a low frictional constant. In order topermit the passage of the lubricant through the disk 57, the latter isprovided with an aperture 72. The upper surface of disk 57 is cut awayto prevent. sticking in its upper position by the binding effectsbetween it and the shoulder 55.

An oil cup 76a is provided to facilitate an oiling of the meetingsurfaces of the lower ball 21 and the ball socket 20 and the collar Inorder to protect these screw threads from the entry of dust and dirtwhile in their is provided. As shown in Figs. 1 and 2, this dirt jacketcomprises the sleeves 80,81, 82

- which fit successively over each other and for that purpose have theinwardly projecting flanges 83 at their respective lower ends, and theoutwardly projecting flanges 84 at their respective upper ends. Theinnermost sleeve 80 is fixed on an upwardly extending collar 39 of thecollar 38 which closes the lower ball. The outer sleeve 82 is guided formovement by a felt packing washer 85 which is held in a grooved link 86carried at the open end of the upper ball 59.

J The method of operation of this raising mechanism is as follows:

During transport, the dump body is in a lowered position as shown inFig. 5 and by the thin dash lines on Fig. 1, and its subframe 14 restson the support 14a secured to the frame 10 (Fi 1a) Upon arriving at theselected point or dumping, the shaft 51 is connected by theaforementioned clutch to the source ofpower, so that the shaft 51 andtherewith the shaft 50 are caused to rotate, and by means of theuniversal joint 49, 48 to drive the stub shaft 44 of this raisingmechanism. The pinion 43 then rotates the toothed ring 31 and causes arotational movement of the outer sleeve 30. This sleeve 30 revolves onits bearing, and attacks by its internal threads the external threads onthe telescoping sleeve 53 at a point which is of lesser diameter thanthe diameter of the upper. ball 59. Likewise the telescoping sleeve 53attacks the threads of the threaded spindle 56, at a diameter which isless than that at which it itself is attacked. The tendency is for theupper ball 59 to remain stationary with regard to its socket casting 60,owing to the greater frictional effect occurring between them inproportion to the friction occurring at the several threadedengagements. The threaded spindle 56 is held stationary with the upperball 59, so that a relative rotation occurs between it and the outersleeve 30, which causes the threaded spindle 56 and the telescopingsleeve 53 to be successively moved upward, and to thrust with them theupper socket casting 60, which being-operatively associated with thevehicle body, will cause this vehicle body to move upward at the pointof attack. Since the vehicle body is pivoted at the point 13, it willtilt rearwardly, under the conditions stated, into the position shown infull lines in Fig. 1. During this tilting, the lower ball 21 will rockabout an axis transverse to the vehicle frame members 10 into theposition shown in Fig. 1, and the stub shaft 44 will move therewith andthe sleeve 27 will be guided in the slot 26, so that although the lowerball 21 rocks, it cannot rotate about an axis substantially in the lineof the collar 30. At the same time, the universal joint 48, 49 and thetelescoping shafts 50, 51 will compensate for this rocking movement andallow a continuity of -power delivery to the pinion 43. whatever be theposition of the lower ball 21. The upper ball 59 is permitted during thetilting movement to rock in a similar manner in its upper casting 60.

As the dump body is constructed, as usual, for dumping either to therear or to the s1de, as shown for example by the body construction of myco ending application Serial No. 740,307 filed ept. 27, 1924, then whenthe body is tilted about its lateral fulcrum, the lower ball 21 may rockabout the axis of the stub shaft 44, and in this case the telescopingshafts and 51 remain substantially in extension of this axis, and nomovement of the universal joint 48, 49 occurs, since under suchconditions the stub shaft 44 is substantially parallel to the underframemembers 10. During such lateral tilting, the same effect occurs betweenthe upper ball 59 and its casting as before, and this ball 59 ispermitted to rock within its casting 60though laterally in thisinstance-to accommodate itself to the changing positions of the dumpbody..

In Fig. 5 is shown the employment of the device with the body holdingand door controlling mechanism of my aforesaid application, to whichreference is made for the method of operation of such features. Thetransverse floor stiffeners 15b in this figure also constitute thegusset plates for the trun-.

nions; and are connected to longitudinal stiffeners, which form inconjunction therewith a rectangular pocket to receive theupper casting60 and to prevent its rotation with regard to the body.

It will be noted that the upper casting 60 is cut away at 75 adjacentits pole of symmetry so that, in the event of wear thereon, the diameterat which the upper ball 59 acts upon the casting 60 will not besubstantially changed, and the frictional resistance between these tworemains constantly greater than the resistance at the threadedengagements.

As the threaded spindle 56 and the telescoping sleeve 53 continue tomove outwardly, their bottom flanges and plates 54 and 57 finally comeinto contact respectively with the shoulders 52 and 55, and finally thedevice is held against any further extension. If the power from theprime mover has not been shut off, the upper ball 59 may slip in itsfrictional engagement in the casting 60, so that no damage occurs to anypart of the system.

During this raising movement, the upward motion of the upper ball 59causes the felt 85 to slide on the outer sleeve 82 of the dirt jacket,or else to cause a relative movement between the several sleeves,according to the respective frictional resistance. In either event, aprogressive extension of the during loading with very dusty material orin the event of discharge of material thereagainst. a

When it is desired to return the vehicle body to its normal horizontalposition, the direction of'rotation of the shafts 51, 50 is reversed,and a reverse efi'ect occurs. The

upper ball 59 is again held by its greater frictional resistance, andthe threaded spindle 56 and the telescoping sleeve 53 retire within eachother and within the outer sleeve 30 until the device has returnedsubstantially into the position shown in Fig. 2.

The bottom of the telescoping sleeve 53 en-' I counters the disk 65 andis prevented from a further downward movement. The stop pins 68 and 67come into contact with each other, and a further downward movement ofthe threaded spindle 56 is prevented. During the latter portion of thesemovements, however, the upper ball 59 is slightly withdrawn from thecasting 60, so'that no shocks or weight are imposed upon the raisingmechanism during the normal transport, since the body 15 and itssubframe 14 rest upon the beam 14a of the underframe 10 duringtransport.

During this return movement, as the upper ball moves down, the feltwasher 85 slides on the upper section 82 of the dirt jacket until thissection comes in contact with the inward surface of the upper ball 59,or else, the frictional engagement between the several flanges of thesections of the telescoping dirt jacket being less, these sections movewith respect to each other.

'In either event, these sections of the dirt jacket collapse one intothe other and downwardly onto the casing 30 until the entire jacket hascollapsed, and now occupies a position wherein it adds nothing to theencumbrance of the raising mechanism, as shown in Fig. 2.

Any appropriate form of thread may be employed for the threaded spindle56 and the telescoping sleeve 53, and the parts, either single ormultiple, are-designed so that the prime mover plant may raise and tiltthe body. More than one telescoping sleeve 53 may be employed ifdesired.

If at any time, by reason of some peculiar condition, the upper ball 59fails to establish a frictional contact with the casting 60 to be heldstationarywith respect thereto,

so that the threaded members may function use, is only needed for aninstant during the raising movement, prior to the engagement of theupper ball 59 with its casting 60: it being understood that duringtransport the ball is normally lowered out of engagement with thecasting 60. When the pin is thus engaged with the outer surface of theball 59, the relative frictional relation between the ball and castingis increased so that the aforesaid threaded movement of the threadedspindle 56 and sleeve 53 may occur.

It is obvious that the form and arrangement of the several parts may bemodified in any wise without departing from the spirit of this inventionwhich is expressed within the scope of the appended claims.

v I claim:

1. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, a lower socket member on said frame, a lower ball movable insaid socket member, a rotatable sleeve journaled in said ball and havingscrew threads therein, a threaded spindle engaging the threads of saidsleeve and adapted to tilt said body, means including a shaft to rotatesaid sleeve, a bearin for said shaft on said lower ball, and a gui e onsaid socket member for said shaft, said guide serving to preventrotation of said ball about the axis of said sleeve and to permitmovements thereofin a plane including said axis.

2. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, interengaging threaded members of said frame, an upper ballconnected to one of said threaded members, an upper socket memberadapted to raise and tilt the dump body, said ball being received insaid socket member, said ball and socket member having cavities thereinadjacent the intersection of the axis of said threaded members with theperipheral surface of said ball and socket member in the transportposition.

3. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, interengaging threaded members supported on said frame andadapted to extend upwardly upon a relative rotation, an upper socketmember, an upper ball received in said upper socket member, means tofixedly secure said upper ball to one of said threaded members,stiffening beams fastened to said dump body beneath its floortransversely and longitudinally thereof to define a chamber within whichsaid socket member is disposed, said beams preventing said socket fromrotational movement, and blocking means supported by the upper socketand engaging said up er ball and one of said beams to frictional y holdsaid upper ball against relative rotation in said upper socket. I

4. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, telescoping members mounted on said frame, an up er socketmember mounted on said dump bo y, an upper ball disposed in ahemispherical cavity in said socket member, a

collar fastened to said socket member to retain said ball against entirewithdrawal from said socket member and collar, the inner surface of saidcollar having a spherical curvature about a center point removed fromthe center point of the spherical curvature of the cavity of said socketmember so that said ball in the telescoping position of said telescopingmembers may be withdrawn from contact with said socket member, and meansfixedly securing said ball to one of said telescoping members.

5. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, telescoping threaded members mounted on said frame, asupporting member mounted on said dump body, a thrust member secured toone of said telescoping members, and frictionally engaging saidsupporting member, and means to increase the frictional resistance torelative movement between said thrust member and said socket.

6. In a raising mechanism for the tiltable dump body of a truck having aframe and a rime mover plant, a lower socket member astened to saidframe, a lower ball movable in said socket, a rotatable sleeve journaledin said socket for movement about an axis assing substantially throughthe center 0 the ball and socket; driving means for said rotatablesleeve including a shaft having its axis at right angles to the axis ofthe sleeve, means on said socket to permit said shaft to rock about, theintersection of its axis wth the axis of the sleeve and to prevent arotational movement of said ball about the axis of the sleeve, aplurality of threaded members engaging in each other and in said sleeveand adapted to be extended and telescoped with respect to said sleeve,an upper ball secured to one of said members, an upper socket membermounted on said body and receiving said ball for frictional engagementtherewith, and means for driving said shaft to said prime mover plant sothat said upper ball may be raised by the relative rotation of saidthreaded members and sleeve during the frictional retention of saidupper ball immovable with said socket, and so that said upper ball maymove in said socket upon the full extension of said telescoping memberswhereby to prevent breakage of the parts.

7. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, a lower socket member fastened to said frame, a hollow lowerball movable in said socket, a rotatable sleeve journaled in said ball,a closing collar for the up er portion of said lower ball to formtherewitli an enclosed lubricatlng chamber, interengagingthreadedmembers in threaded engagement with the interior of said sleeve, meanscarried by one of said members to raise and tilt the dump body, andmeans to rotate said sleeve, said sleeve and members having lubricatingpassages therein leading from the chamber of sald ball to the bearingsurfaces, said interengaging threaded members forming a pump and servingduring the extension and collapsing to force and bring the lubricatingmaterial to such contacting surfaces.

8. In a raising mechanism for the tiltable body of a vehicle, a frame, ascrew hoistlng mechanism mounted on said frame and adapted to tilt saidbody upon extension, means to drive said screw mechanism whereby toproduce such tilting, said screw mechanism having a frictionalconnection with the dump body of a resistance greater than theresistance of threads during the relative movement, andmeans in saidscrew mechanism to block further relative movement of said threads atthe limit of extension of said screw mechanism whereby said threads turnas a unit, said frictional connection permitting such rotation as aunit.

9. In a raising mechanism for the tiltable dump body of a vehicle havinga frame, telescoping members mounted on said frame, an ltipper socketmember mounted on said dump an upper ball disposed in a hemispher1-- calcavity of said socket member, a collar fastened to said socket member toretain said ball against entire withdrawal from said socket member andcollar, the inner surface of said collar being spaced from the ball whenthe latter is engaged in the hemispherical cavity, so that said ball ina telescoping position of said telescoping members may be withdrawn fromthe contact with said socket member, and means fixedly securing saidball ,to one of said telescoping members.

10. In a raising mechanism for the tiltable dump body of a vehiclehaving a frame, telescoping threaded 'members mounted on said frame, asupporting member mounted on said dump body and held against rotationabout the axis of said threaded members, a

th'rust member secured to one of said telescoping members and heldfixedly thereto for rotation therewith, said thrust member of saidthreaded members, and positive means i to move said thrust memberthrough said threaded members, whereby the positive driving means willcause the extension of said threaded members and the raising of the dumpbody until the limiting means operates, and thereafter will cause aslippage between the supporting member and thrust member at thefrictional engagement between the same.

' 11. In a raising mechanism for the tiltable dump body of a vehiclehaving a frame, interengaging threaded members carried by said frame andadapted to rock in lon tudinal and transverse planes relative to t evehicle, an upper ball carried by one of said members and adapted to beraised during the relative rotation of said threaded members, an uppersocket member carried by the body and engaging said upper ball so thatthe ball may rock and rotate with respect thereto, said upper ball andsocket including means to maintain the frictional resistance between theupper socket and upper ball greater than the frictional resistance tomovement between said interengaging threaded members during thenormalmovement thereof, means i to limit the relative threading movementof said members, said friction producing means permitting the relativerotation of said up er socket and upper ball after said threa ed membershave reached their limit of travel.

12. In a raising mechanism for a tiltable dump body of a vehicle havinga frame, a screw hoisting mechanism mounted thereon, said hoistingmechanism including telesco ing parts to raise and lower the dump b0 y,a socket member attached to the body and a ball carried by one of thetelescoping members held in rotatable engagement in said socket, meansfor frictionally holding said ball against rotation in the socket memberwhen the hoisting mechanism is subjected to normal turning stress, andmeans for limiting the movement of said telescoping members, saidfrictional means being adapted to yield to permit the ball to rotate insaid socket should the telescoping parts reach eitherlimit internalthreads, a first threaded member en-- gaging in said threaded sleeve anditself having internal threads, a second threaded member engaglngintheinternal threads of said first threaded inemberj,--a closing plate forthe bottom of said sleeve, a first stop pin mounted on said closingplate eccentric to the axis of said sleeve and threaded members, andasecond stop pin on said second threaded member. similarlyeccentrictosaid axis and adapted to engage said first stop in the collapsedcondition of said members and sleeve to prevent a further relativerotational movement between said sleeve and said sec-- ond threadedmember. l4, Ina raising mechanism for the tiltable dumpbody of a vehiclehaving a frame, a lower socketmember fixedly j mounted on form alubricant reservoir and havin an aperture at its top and being 'rockab ein said socket, an internally threaded rotatable sleeve passing throughsaid aperture and mounted in said ball, thrust bearings for said sleevein said ball, and radial bearing members in spaced relationship tooneanother carried by said ball and enga ing said sleeve above and belowsaid thrust earing, one of said guide members forming a closing collarat the aperture of said ball whereby to close the reservoir, said sleevehaving an aperture to permit the passage of lubricant from the reservoirinto the sleeve, a threaded member engaged with the threads of saidsleeve and adapted to perform a movement of extension and collapsingduring rotations of said sleeve, said threaded memberoperating in saidsleeve to move the lubricant therein.

15. In a raising mechanism for the tiltable dump body of a vehiclehaving a frame, a screw hoisting mechanism mounted on said frame andcomprising threaded interengaging and relatively extensible members andmeans to limit the relative rotational threading movement of saidmembers when collapsed and when extended, and a rotatable connectionbetween a. first one of said members of the screw mechanism and saidbody having frictional resistance against relative rotation of its partswhich is greater than the frictional resistance between the threadedmembers against relative rotational and threading movement at allintermediate positions of the screw mechanism between full extension andfull collapsing, whereby said rotatable connection prevents the turningof said first member with respect to said body at such intermediatepositions-but permits such turning at the limits of movement of saidmembers whereby breakage of parts at said limits of travel is avoided.

16. In a raising mechanism for the tiltable body of a vehicle having aframe, a screw hoisting mechanism mounted on said frame and includinginterengaging threaded members adapted to extend and collapse byrelative rotational threading movement, means to prevent relativerotation of said members at a predetermined limit of extension whereby tey are coupled ositively together, a.- connection between a rst one ofsaid members and a prime mover plant whereby to produce a rotation ofsaid first member, and

a connection between a second one of said members and said bodyincludingfrictional means to hold said second member a ainst movementwith respect to said body uring the relative rotational movement of saidmembers, said frictional connection permitting the relative movement ofsaid second member with respect to said body after the operation of saidrotation preventing means,

In testimony whereof I aflix my signature.

' HENRY FORT FLOWERS.

